Index: /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsGroup.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsGroup.cpp	(revision 84622)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsGroup.cpp	(revision 84623)
@@ -89,7 +89,9 @@
 
     /* Cleanup superflous items: */
-    bool fCleanupPerformed = m_items.size() > m_machineItems.size();
+    const bool fCleanupPerformed = m_items.size() > m_machineItems.size();
     while (m_items.size() > m_machineItems.size())
         delete m_items.last();
+    foreach (UIDetailsItem *pItem, m_items)
+        pItem->toSet()->clearSet();
     if (fCleanupPerformed)
         updateGeometry();
Index: /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsSet.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsSet.cpp	(revision 84622)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsSet.cpp	(revision 84623)
@@ -62,4 +62,12 @@
     /* Remove set from the parent group: */
     parentItem()->removeItem(this);
+}
+
+void UIDetailsSet::clearSet()
+{
+    /* Clear passed arguments: */
+    m_pMachineItem = 0;
+    m_comMachine = CMachine();
+    m_comCloudMachine = CCloudMachine();
 }
 
@@ -568,4 +576,8 @@
         return;
 
+    /* Make sure VM is set: */
+    if (m_comMachine.isNull())
+        return;
+
     /* Is this our VM changed? */
     if (m_comMachine.GetId() != uId)
@@ -582,4 +594,8 @@
         return;
 
+    /* Make sure VM is set: */
+    if (m_comMachine.isNull())
+        return;
+
     /* Is this our VM changed? */
     if (m_comMachine.GetId() != uId)
@@ -594,4 +610,8 @@
     /* For local VMs only: */
     if (!m_fIsLocal)
+        return;
+
+    /* Make sure VM is set: */
+    if (m_comMachine.isNull())
         return;
 
Index: /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsSet.h
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsSet.h	(revision 84622)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/manager/details/UIDetailsSet.h	(revision 84623)
@@ -55,4 +55,6 @@
     /** @name Item stuff.
       * @{ */
+        /** Cleanups set, wiping out machine-item and [cloud]machine information for good. */
+        void clearSet();
         /** Builds set based on passed @a pMachineItem.
           * @param  fFullSet  Brigns whether full set should be built.